Mechanically keyed optical organ

ABSTRACT

An optical organ of the type which shines light through the tracks of a rotating optical record onto photocell apparatus and which utilizes depressable keys to play selected tracks, wherein only one or a few photocells are required. The keys are connected to slideable rods that deflect small light control members positioned between the record and photocell. In one organ, the deflectable members are pivotally mounted shutters with corrugated side walls that interfit one another to prevent the leakage of light between the shutters. In another organ, the deflectable members are resilient light-conducting fingers formed in a sheet-like edge portion of a transparent member, each finger being deflectable to a position where its end can pick up light from a particular optical track and carry it to the photocell.

United States Patent 1 Bartok et al. Y I

[ll] Aug. 7, 1973- MECHANIC'ALLY KEYED OPTICAL ORGAN [75] Inventors:Stephen Bartok, Gardena; Melvin R.

- Kennedy, Carson; George J. Klose,

Redondo Beach; Edmund E. Landsinger, Torrance; George W. Stewart, CostaMesa, all of Calif.

[73] Assignee: Mattel, Inc., HawthorneyCalif.

[22] Filed: Sept. 28,1972

[21] Appl. No.: 293,217

[52] US. Cl. 84/118 [51] Int. Cl. G10h 3/06 [58] Field of Search 84/1.l8

[56] g 7 References Cited UNITED STATES PATENTS 2,734,416 2/1956 Corwiri84/1.l8 X 2,946,252 7/1960 Clark 84/l.l8 X 3,250,844 5/1966 Rieth ..t84/l.l8 2,586,664 2/1952 Knoblaugh... 84/l.18 2,796,534 Williams..84/l.l8 X

Primary Examiner Richard B. Wilkinson Assistant ExaminerLawrence R.Franklin Attorney-Seymour A. Scholnick 571 I ABSTRACT An optical organof the type which shines light through the tracks of a rotating opticalrecord onto photocell apparatus and which utilizes depressable keys toplay selected tracks, wherein only one or a few photocells are required.The keys are connected to slideable rods that deflect small lightcontrol members positioned between the record and photocell. In oneorgan, the deflectable members are pivotally mounted shutters withcorrugated side walls that interfit one another to prevent the leakageof light between the shutters. In another organ, the deflectable membersare resilient light-conducting fingers formed in a sheet-like edgeportion of a transparent member, each finger being deflectabie to aposition where its end can pick up light from a particular optical trackand carry it to the photocell.

16 Claims, 16 Drawing Figures PAIEmmAuc mza 33,51,573

' sum 2 us 6 PAHNIED nus ma SHEET 5 0F 6 PMBNIEDMM; Tms

SHEET 6 BF 6 1 MECHANICALLY KEYED OPTICAL ORGAN BACKGROUND oE'rnEINVENTION This invention relates to optical organs.

Optical organs of'moderate cost can be constructed by utilizing a discrecord containing numerous concentric optical, tracks. As the disc isrotated, light shines through the tracksonto photocell apparatus whichgenerates electrical signals that are amplified and which drive aloudspeaker. It is inherent that an organ contains numerous keys thatcan be selectively operated to play different sounds, and it isnecessary to connect each key so that a corresponding optical track isplayed only when that key is depressed. The cost of providing suchconnections is considerable because even relativelysimple organs thatare to be more than mere toys require a large number of optical tracks,such as 50, and a corresponding number of keys or buttons. Also, theoptical tracks are closely spaced from one another on the opticalrecord, so that the connecting devices must be small.

One type of optical organ utilizes a large number of tiny photocells,one photocell being positioned opposite each track of the record to pickup light only from that track. A large number of electrical conductorsextend from the photocells to the numerous keys, and an electricalswitch is provided at each key to control the passage of current from acorresponding photocell to an amplifier. The cost of the numerousphotocell switches and their interconnections is considerable. Inaddition, problems of stray current pickup are encountered due tocurrents, since they received light through a very thin slit, andbecause these currents must travel a considerable distance to theswitches at the keyboard.

SUMMARY OF THE INVENTION In accordance with one embodiment of thepresent invention, an optical organ is provided for use with an opticaldisc record that has numerous closely spaced optical tracks, whichutilizes a relatively simple and economical apparatus for controllingthe playing of the different tracks from the manually depressable keys.The organ includes numberous closely spaced rods slideably mounted onthe frame of the organ, each rod having an inner end connected to a keyso that depression of the keycauses the rod to slide along its length.The opposite ends of the rods abut a row of light shutters whichnor'mally'block the passage of light from the record tracks 'toaphotocell. When a key is depressed to slide a corresponding rod, the rodmoves a corresponding shutter out of a blocking position so that lightfrom a corresponding record track can fall on the phoparticularity inthe appended claims. The invention will best be understood from thefollowing description when read in conjunction with the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of anorgan constructed in accordance with one embodiment of the presentinvention, with motions of the organ housing removed to show some of theinternal mechanisms;

FIG. 2 is a partial substantially front sectional view of the organ ofFIG. 1;

FIG. 3 is a view taken 'on the line 3-3 of FIG. 2;

FIG. 4 is a view taken on the line 4-4 of FIG. 2;

FIG. 5 is a partial perspective view of the mechanism of FIG. 2;

FIG. 6 is a partial plan view of the organ of FIG. 1;

FIG. 7 is a partial front elevation view of the key board in the organof FIG'. .1;

FIG. 8 is a view taken on the line 8-8 of FIG/7;

FIG. 9 is a view taken on the line 9-9 of FIG. 7;

FIG. 10 if a partial perspective view of the keyboard linkage of theorgan in FIG. 1;

FIG. 11 is a partial perspective view of the chord section linkage;

FIG. 12 is a partial perspective view of an organ constructed inaccordance with another embodiment of v the invention;

tocell. A single photocell picks up all light that passes by theshutters. The shutters have corrugated side portions that interfit oneanother to prevent the leakage of light between the shutters.

In another embodiment of the invention the passage of light to thephotocells is controlled by numerous light conducting fingers that canbe individually deflected to conduct light from corresponding record.

FIG. 13 is a partial sectional view of the organ of FIG. 12;

FIG. 14 is a partial perspective view of the chord section linkage ofthe organ of FIG. 12;

FIG. 15 is a sectional view taken on the line l515 of FIG. 14; and

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 illustrates an organ 10which utilized a changeable optical disc record 12 that containsnumerous concentric optical tracks and that is rotated by a motor drivenwheel 13. Some of the tracks define sustained notes of different pitcheswhile other'tracks define accompaniment patterns of notes. The organincludes a piano type keyboard 14 with numerous keys 16 that can beselectively depressed by a musician to play one of the optical tracksthat represents 'a sustained tone. That is, the depression of one of thekeys 16 results in the sounding of a corresponding note. The organ alsoincludes a chord section 18 with numerous button-like keys 20 that alsocan be manually depressed by a musician. Depression of one of the keysor buttons 20 results in a corresponding record track being played whichdefines an accompaniment sound. The sounds are produced by shining lightthrough all of the record tracks as the record rotates, and by pickingup the light with a photocell. Each record track varies in width, so thetracks create light beams which time vary in predetermined patterns. Acompact playing head apparatus 22 permits the selection of particulartracks by controlling the passage of light to the photocell. Linkingmechanisms connect the keys 16 of the keyboard and connect the buttons20 of the chord section, to the playing head apparatus 22, so that thepassage of light from a particular record track to the photocell occursonly when a corresponding key or button is depressed by the musician.

FIGS. 25 illustrate details of the playing head apparatus'22. A lamp 24lies beneath the record 12 and shines light through the record, througha narrow slit 26 in a mask 28, through a collimator 30 and onto a pickupregion 32. A light collector 34 is positioned with a light-receiving endthereof at the pickup region 32. The light collector 34 carries lightreceived at the pickup region 32 to a photocell 36. The photocellgenerates currents corresponding to the light incident thereon andpasses the currents through a pre-amplifier 38 and a volume control 40to an amplifier 42 that drives a loudspeaker 44.

Normally, all light passsing through the tracks of the record 12 areprevented from reaching the pickup region 32 by a row of shutters 46.Each shutter has a blocking portion 48 that normally lies between therecord 12 and the pickup region 32. The shutters are pivotally mountedon a shaft 50 that extends through holes in the shutters, and eachshutter also has an operating end 52 opposite the blocking portion 48.The operating end 52 of each shutter can be deflected to cause theshutter to pivot and move the blocking portion 48 out of a blocking.position. This permits light from one of the optical tracks to reach thepickup region 32 and therefore to be received by the photocell 36. Aspring member 54 has numerous spring fingers 56 bearing against theoperating ends of the shutters to urge them toward a blocking position.The spring member 54 as well as the axle 50 are fixed to a head mount 58that is fixed to the frame 60 of the organ.

The deflection of the shutters 46 is controlled by pivoting of the keys16. Each key is pivotally mounted on the organ frame 60 so that when aforward end of a key is depressed, a crank 62 pivotally mounted on theframe pivots and causes a long rod 64 to slide along its length. Theorgan includes numerous rods 64, each having an outer end 66 that bearsagainst the operating end 52 of a corresponding light shutter. When therod 64 slides along its length towards the head assembly 22, it deflectsa corresponding light shutter 46 to an unblocking position, so thatlight from a corresponding track of the record 12 can reach the pickupregion 32 for transmission to the photocell 36. Thus, the depression ofany key 16 of the keyboard results in the playing of a correspondingrecord track.

The rods 64 slide along a bearing plate 68 of the frame and pass throughholes 70 formed in the head mount 58, so that the positions of the outerends 66 of the rods are closely controlled. The mounting of the rods andtheir connection to the keys 16 is best illustrated in FIGS. 6-9. Eachkey 16 of the keyboard has a recess 71 near its rearward end, where itreceives and is pivotally mounted on a pivot bar 72 of the frame. Aspring 74 urges the key to pivot in a direction to cause its forward endto move up. The key also has an arm 76 that extends downwardly from amiddle portion of the keY and which is pivotally connected to an arm 78of the crank 62. The crank 62 is pivotally mounted on a trunnion 82 ofasupport bar 86 of the frame. The crank also has a downwardly extendingarm 88 that is engaged with an inner end 90 of a rod 64. When the key 16is depressed, the crank 62 pivots so that its downwardly extending arm88 moves towards the playing its original position. It may be noted thatthe crank 62.

not only connects the key to a rod, but also serves to stabilize the keyagainst shifting and wobbling.

The numerous keys 16 of the keyboard are all pivotally mounted on theframe and coupled to their respective rods 62 in the same manner. It isdesirable to construct the organ so that the distance between the frontof each white key and the pivot point is the same for all keys, and thedistance between the front of each white key and the location where itis coupled by a crank to a rod 64 is the same for all keys. This allowsall of the white keys to have the same feel, that is, it provides allkeys with the same resistance to depression and results in a uniformdistance of key depression to cause playing of notes. A similaruniformity is desirable for all black keys.

The pivot bar 72, which pivotally supports the keys, and the bar 86, onwhich the cranks are mounted, extend parallel to one another along thewidth of the organ frame. The rods 64, however, extend at a slight angleA such as 3 from an imaginary laterally extending line. The angle A ischosen so that for a given spacing of the keys from one another alongthe width of the keyboard, such as an inch, the outer ends 66 of therods will bespaced from one another in a direction perpendicular totheir length by distances equal to the spacing of the record tracks,such as 0.05 inch. This slight angling of the rods 64 provides a closebut sufficient spacing to accommodate a large number of thin rods on theorgan frame. All of the cranks 62 are identical and are identicallyconnected to their respective keys and rods. The rods 64 are all ofdifferent lengths, but they are otherwise identical. The rods 64 can beformed from standard straight rods by cutting off lengths of therequired size and forming their inner ends with identical bends. Therods can be easily formed at low cost, and require a minimum of toolingeven though a large number of rods is used in each organ and'all of therods are different in length.

One of the problems that can be encountered in the use of numerous lightshutters that are closely spaced from one another, is that light cansometimes leak between the shutters and be picked up by the photocell.The amount of light that can leak between the shutters is very smallwhere the shutters are accurately constructed and mounted, so that theleakage light creates a sound of such low intensity that it is notnoticeable when any of the tracks is being played. However, when none ofthe tracks is being played and it is desired to create no sound at all,even a low level of light leakage can create an audible sound that canbe annoying.

In order to minimize leakage, the shutters are constructed asillustrated in H0. 4, with corrugated sides 48 at their blockingportions, and withthe corrugated sides interfitting one another. Theinterfitting corrugated sides greatly reduce the amount of lightleakage, so that the organ is much quieter when none of the keys isbeing depressed. If desired, electrical circuitry can be provided thatprevents any signals from reaching the amplifier if the signals are ofan extremely low amplitude which is less than results from playing atrack, or mechanical devices can be utilized to sense when at It wouldbe possible to utilize the same light collector 34 and photocell 36 forboth the optical tracks played by keys 16 of the keyboard and the tracksplayed by buttons of the chord section. However, the present organutilizes a separate light collector and photocell in order to allowindependent control of the voluine of the keyboard section andof thechord section. As illustrated in FIG. 2 and 5, a separate lightcollector 100, photocell 102, preamplifier 104 and volume control 106are utilized for the chord section. In addition, a separate row ofshutters 108 is utilized which is substantially identical to theshutters 46. The chord section shutters 108 are moved by'rods 110 whichare slideably mounted on the frame. and which deflect the shutters 108in the same manner as the rods 64 deflect their shutters 46. A differentmechanism, however, is utilized to convert depressing forces applied toa chord section button 20 into sliding movement of a chord sec- 7 tionrod 110.

. cover plate 114. The button is constantly urged upwardly by a spring116 which extends between a lower end of the button and a spring holder118 formed on a mounting plate 120 of the organ frame. A linking memberor rod 122a which'is pivotally mounted on a pair of upstanding flanges124, 126, extends through a slot 128 formed in the button, so that whenthe button 20a is depressed, the linking rod 122a is pivoted. Thelinking rod 122 is formed with an arm 130 that is received in a slot 132of the mounting plate 120. The chord section rod 110a is slideablymounted in recesses 134 formed on the mounting plate, and has a bend 136lying in theslot 132. The bend 136 forms a return curve with a pair oflegs 138, 140, and the arm 130 of the linking rod lies between theselegs 138, 140. When the rod 122 pivots, in response to the depression ofthe button 20a, the arm 130 pushes against an arm 140 of the chordsection rod 110a and causes the rod to slide along its length. When thebutton 20a is released, the arm 130 pushes against the other leg 138 ofthe rod 110a to return it to its original position.

The chord section includes numerous buttons 20 that are mounted closetogether, as illustrated in FIG. 11. Each of the buttons is mountedsimilarlY to button 20a and is connected by a corresponding linking rod122 to a corresponding chord section rod 110. The organ is constructedso that some of the chord buttons 20 play the same record tracks. Thus,the chord section rod 1100 has a second bend 142 where it receives anarm of another linking rod 122b.

The chord section apparatus can be constructed at relatively low cost,because it utilizes a minimum of parts, and because most of the partsare identical. Thus, a single mounting plate 120 can be utilized, whichcan be formed with numerous slots, and the buttons 20 all can beconstructed and mounted identically. The major different parts are thelinking rods 122 and the chord section rods 110. These rods all can beconstructed from simple rods of the same kind that are used for thekeybaord rods, by merely cutting and bending the rods at appropriateplaces. Thus, even though the numerous buttons of the chord sectionrequire numerous conat low cost.

. 6 necting devices, the chord section can be constructed FIGS.x12-16illustrate another organ constructed in' accordance with the invention,which utilizes numer-- ous light transmitting members or fingers150,that can carry light from an optical track to a common photocell152. Unlike the light shutters of theprevious'embo diment of theinvention, the movable members l50.do not block the passage of light butinstead carry the light. The fingers are formed on a sheet-like edgeportion 154 of an optical member 156, the edge portion 154 havingnumerous parallel slits that form the fingers 150. A mask 158 blocks thepassage of light from the record 12 to the ends of the fingers 150. Themask 158 has a slit 160 spaced a slight distance from the ends 152 ofthe light fingers when the fingers are in their-nondeflected positions.Each of the fingers 150 can be deflectedto a position where its extremeend or tip, 162 lies over the slit 160 and can pick up light andtransmit it to the photocell 152. Where the record 12 is spacedappreciably from the maskand light fingers, a collimator can-be utilizedto assure that only light from one track reaches the tip 162 of -acorresponding light finger when the light finger is over the slit 160.

The light fingers 150 are deflected by rods 164 that are mounted forsliding along their length on the organ. The outer ends 166 of the rodspass through holes in a guide 168 and can push against the light fingersto deflect them. It may be noted that the light fingers are constructedwith smooth exterior surfaces so that they pick up light only at theirtips 162. Furthermore, if necessary, the light fingers and even the restof the optical member 156 can be coated with a film of aluminum orsilver to prevent pick up of light except at the tips of the fingers andto reduce losses of light picked up thereat.

length of the rod 164 to slide and thereby deflect a light 7 finger.

FIGS. 13-16 illustrate details of a chord sectionasr sembly whichincludes button-like keys or buttons 182 that slide up and down.Depression of each of the buttons results in sliding of a correspondingrod portion 184 that deflects a corresponding light finger 186 ofanother optical member 188 which carries light to another photocell 190.a stack of plates 192 is slideably mounted beneath the buttons 182, andthe rod portions 184 that deflect the light fingers are formed by thinconnecting regions 198. The guides 194 are constructed of flexiblematerial such as polypropylene so that the connecting regions 198 serveas hinges. Each of the fingers 196 extends through slots formed in theplates 192. Most of the slots 200 in the plates are long, but each platecarries at least one narrow slot 202 which is shorter than the others.When a button such as button 128a is depressed, a corresponding finger196a is pivoted and it moves sidewardly through all of the slots.Onlyone of the slots 202a in the plate 192a is short enough, so that afinger 196a will push the plate sidewardly. Accordingly, only thatplate192a will shift sidewardly so that its' rod portion 184a will deflect acorresponding light finger 1860.

The use of an optical member with a sheet-like edge portion divided intonumerous optical fingers can simplify the organ construction. Thenumerous optical fingers 154 on the optical member 156 can be formedintegrally with one another by injection molding or other formingoperations, and the mounting of the fingers is simplified since only thesingle member 156 need be accurately mounted. A variety of opticalmaterials can be utilized, such as Lucite plastic, which can transmitlight and which are sufficiently flexible.

Thus, the invention provides a simplified optical organ utilizingdeflectable elements to control the passage of light from numerousclosely spaced optical tracks of a record to one or some other limitednumber of photocells. The deflection of the light controlling members isaccomplished by the use of simple rods which are slideably mounted onthe organ frame. In the case of the keyboard, particularly, the use ofnumerous rods that extend parallel to one another and which are closelyspaced from one another, permits the construction of a compact organusing low cost components. The rods have outer ends adjacent to thedeflectable members and have inner ends that are connected to the samelocations at all of the keys of the keyboard, so that all of the keyshave the same feel. The rods are slideably mounted on the frame so thatthey extend at a small angle from an imaginary laterally extending linewhich is parallel to the axes of pivoting of the keys on the keyboard.Rods can be utilized atthe chord section by forming them with bends thatare received in slots of a mounting plate, and by utilizing additionallinking rods connected to the chord buttons to slide the chord sectionrods that deflect the shutters. In one organ, light shutters areutilized which are deflected by the rods. The light shutters havecorrugated and interfitting side walls to minimize the leakage of lightaround them. In another embodiment of the invention, the light controlmembers actually carry light at least part of the way along the lightpath extending from the optical track to the photocell. The lightcarrying members or fingers can be deflected from a normal positionwherein they do not carry light along this path to a position to carrylight therealong. The light fingers can be formed along an edge portionof a unitary optical member, so that the fingers are formed integrallyand are mounted in a simplified manner. The fingers can be mounted sothat tips thereof which can pick up light are normally spaced from aslit in a mask, but the fingers being deflectable over the slit to pickup light from the optical tracks.

Although particular embodiments of the invention have been described andillustrated herein,- it is recognized that modifications and variationsmay readily occur to those skilled in the art and consequently it isintended that the claims be interpreted to cover such modifications andequivalents.

What is claimed is:

1. An organ comprising:

a frame;

means mounted on said frame for rotating an optical record that hasnumerous closely spaced optical tracks;

a light source on said frame for shining light through the opticalrecord;

8 light pickup means including a photocell, positioned .on a side of therecord opposite the light source for generating electrical signalscorresponding to the light reaching the light pickup means; I aplurality of closely spaced shutters movably mounted .on the frame, eachshutter pivotable between a blocking position wherein it blocks thepassage of light from an optical track. to the light pickup means, andan unblocking position spaced therefrom;

I spring means for urging said shutters toward said blocking positions;

a plurality of rods slideably mounted on said frame for sliding alongtheir length, each rod having a first end which bears against one ofsaid shutters and an opposite second end; and

a plurality of manually depressable keys coupled to said second ends ofsaid rods to slide them along their lengths.

2. The organ described in claim 1 wherein said shutters have endportions normally lying between the record and light pickup means, whichhave corrugated sides that interfit one another.

3. The organ described in claim 1 wherein:

said shutters are pivotally mounted on a common axle that is mounted onthe frame and that extends through holes in the shutters; and

said first ends of said rods abut portions of the-shutters which lieopposite the shutter portions that normally block light from passingfrom the record to the pickup means.

4. An organ comprising:

means defining a plurality of light pickup regions;

means for directing a plurality of light beams which time vary inpredetermined patterns at said pickup regions;

photocell means responsive to light at said pickup regions forgenerating electrical currents;

means responsive to said photocell means for generating sounds;

a plurality of light shutters selectively movable between first andsecond positions wherein they respectively block or unblock said lightbeams from reaching said pickup regions; and

manually operable means for moving said shutters, said shutters havingcorrugations on opposite sides that interfit the corrugations onadjacent shutters,

' whereby to minimize leakage of light between shutters.

5. An organ comprising: 1

a frame having a forward portion and opposite side portions; 7

an elongated keyboard extending laterally along said forward portion ofsaid frame and having a plurality of keys spaced from one another alongthe length of the keyboard;

means for pivotally mounting said keys on said frame;

means defining a plurality of light pickup regions at a location on saidframe which is substantially at one side of said keyboard;

means for directing a plurality of light beams which time vary inpredetermined patterns at said pickup regions;

photocell means responsive to light received at said light pickupregions for generating electrical signals;

means responsive, to the output of said photocell means for generatingsounds; light control means including a plurality of elements movablymounted at said pickup region, each element movable between first andsecond positions to respectively pass or not pass one of said lightbeams to said photocell means; and I means for coupling said keys tosaid elements to move them, including a plurality of rods slideablymounted on said frame, said rods extending parallel to one anotherprimarily in a direction parallel to the length of the keyboard but at asmall angle with the length of the keyboard, each rod having an outerend coupled to one of said elements to move it and an inner end, saidmeans for coupling also including connecting means coupling the innerends of the rod to locations on said keys spaced a uniform distance fromthe axis of pivoting of the keys on the keyboard, whereby to providesubstantially the same resistance to depression and substantially thesame distance of depression for the keys. 6. The organ described inclaim wherein: said light control means includes a light conductingmember constructed of flexible light-conducting material, said memberhaving an edge portion containing a plurality of slits dividing it intoa plurality of flexible light conducting fingers that form saidelements, the ends of said fingers normally spaced from said pickupregions but deflectable to said pickup region to receive light; and theouter end of each rod lies adjacent to a different one of said fingers,so that when the rod is slid along its length toward a correspondingfinger the rod deflects the finger to a pickup region. 7. The organdescribed in claim 5 wherein: said elements of said light control meansincludes a plurality of shutters pivotally mounted on the frame to blockand unblock the passage of light between said pickup regions andphotocell means; and I the outer end of each rod lies adjacent to adifferent one of said shutters, so that when the rod is slid along itslength towardsa corresponding shutter, the rod pushes on a shutterportion to pivot the shutter to an unblocking position.

8. The organ described in claim 5 wherein said means for couplingincludes pairs of cam members, one member of each pair mounted on eachkey and the other mounted on the frame, said cam members extendingacross one another, and the inner end of a corresponding rod extendingsubstantially perpendicular to mostof its rod length and lying betweenthe pair of cam members, so that depression of a key urges sliding ofthe rod along its length.

9. The organ described in claim 5 wherein: eachof said keys iselongated, extends perpendicular to the length of the keyboard, andpivots about an axis perpendicular to the length of the key; and saidmeans for coupling includes a plurality of cranks pivotally'mounted onthe, frame about axes substantially perpendicular to the axis ofpivoting of the keys, each crank having a first armopivot'ally coupledto the key and another arm pivotally coupled to an inner end of a rod,whereby the rods help stabilize the positions of the keys.

10. An organ comprising:

means defining a plurality of light pickup regions;

means for directing a plurality of light beams which time vary inpredetermined patterns at-said pickup regions; l g

photocell means responsive to light received at said pickup regions forgenerating electrical signals;

a plurality of light control elements movably mounted at said pickupregions, each element movable between first and second positions torespectively pass or not pass one of said light beams to said photocellmeans;

a plurality of manually depressable members; a plurality of rods mountedto slide along their length, each rod having an outer end disposedagainst one of said light control elements, and each rod having an innerend portion that is bent in a return curve which forms a pair of legsspaced along the length of the rod; and

plurality of pivotally mounted linking members,

each having a first arm coupled to one of said depressable members to bepivoted by it and each having a second arm extending between the legs atthe inner end of a rod.

11. The organ described in claim 10 including a frame apparatus havingfirst bearings pivotally supporting said linking members about axessubstantially perpendicular to said rods, and having a plurality ofnarrow elongated recesses each extending parallel to a rod and receivingsaid bent inner end portion of the rod, the second arm of each linkingmember extending into a corresponding slot.

12. An organ comprising:

means defining a plurality of light pickup regions;

means for directing a plurality of light beams which time vary inpredetermined patterns at said pickup regions;

photocell means for converting light into electrical signals;

light conducting means for conducting light from said light pickupregions to said photocell means, ineluding a plurality of elongatedlight conducting elements individually movable between first positionswherein they carry light along at least part of a path that extends froma corresponding light pickup region to said photocell means and secondpositions wherein they do not carry light from the light pickup regionto the photocell means;

keyboard means having a plurality of manually operable keys;

means coupling said keys to said light conducting elements forselectively moving said elements in response to operation of said keys;and

means responsive to the output of said photocell means for generatingsounds.

13. The organ described in 'claim 12 wherein said light conducting meansincludes a member constructed of resilient light conducting materialhaving an edge portion with a plurality of slots therein dividing itinto a plurality of fingers forming said light conducting elements.

14. The organ described in claim 12 wherein:

said means defining a plurality of light pickup regions includes meansdefining a slit for blocking light except along a predetermined path;and

said light conducting elements have end portions which lie over and awayfrom said slit when the elements are respectively in said first andsecond posi ceive any light picked up by any of said optical fintions. igers; Organ for use with optical record p speaker means coupled to saidphotocell means for h1g1 generating sounds; and

a frame; 5 manually operable means for selectively deflecting means forrotating an optical record on said frame; said optical fingers betweenpositions away from means for shining light through said optical record;

means for masking a region at a side of the optical record opposite saidmeans for shining light, except for an elongated pickup area;

a light collector having a sheet-like edge portion containing aplurality of slits that divide the edge porand over said pickup area.

16. The organ described in claim wherein said manually operable meansincludes a plurality of rods slideably mounted on said frame, said rodshaving outer ends adjacent to said optical fingers to deflect them andtion into a plurality of optical fingers, said light colhaving innerends, and said manually operable means lector mounted on said frame withthe nds f h also includes manually depressable members coupled fingersnear said elongated pickup area; 15 to said rods to slide them along'the frame.

photocell means coupled to said light collector to re-

1. An organ comprising: a frame; means mounted on said frame for rotating an optical record that has numerous closely spaced optical tracks; a light source on said frame for shining light through the optical record; light pickup means including a photocell, positioned on a side of the record opposite the light source for generating electrical signals corresponding to the light reaching the light pickup means; a plurality of closely spaced shutters movably mounted on the frame, each shutter pivotable between a blocking position wherein it blocks the passage of light from an optical track to the light pickup means, and an unblocking position spaced therefrom; spring means for urging said shutters toward said blocking positions; a plurality of rods slideably mounted on said frame for sliding along their length, each rod having a first end which bears against one of said shutters and an opposite second end; and a plurality of manually depressable keys coupled to said second ends of said rods to slide them along their lengths.
 2. The organ described in claim 1 wherein said shutters have end portions normally lying between the record and light pickup means, which have corrugated sides that interfit one another.
 3. The organ described in claim 1 wherein: said shutters are pivotally mounted on a common axle that is mounted on the frame and that extends through holes in the shutters; and said first ends of said rods abut portions of the shutters which lie opposite the shutter portions that normally block light from passing from the record to the pickup means.
 4. An organ comprising: means defining a plurality of light pickup regions; means for directing a plurality of light beams which time vary in predetermined patterns at said pickup regions; photocell means responsive to light at said pickup regions for generating electrical currents; means responsive to said photocell means for generating sounds; a plurality of light shutters selectively movable between first and second positions wherein they respectively block or unblock said light beams from reaching said pickup regions; and manually operable means for moving said shutters, said shutters having corrugations on opposite sides that interfit the corrugations on adjacent shutters, whereby to minimize leakage of light between shutters.
 5. An organ comprising: a frame having a forward portion and opposite side portions; an elOngated keyboard extending laterally along said forward portion of said frame and having a plurality of keys spaced from one another along the length of the keyboard; means for pivotally mounting said keys on said frame; means defining a plurality of light pickup regions at a location on said frame which is substantially at one side of said keyboard; means for directing a plurality of light beams which time vary in predetermined patterns at said pickup regions; photocell means responsive to light received at said light pickup regions for generating electrical signals; means responsive to the output of said photocell means for generating sounds; light control means including a plurality of elements movably mounted at said pickup region, each element movable between first and second positions to respectively pass or not pass one of said light beams to said photocell means; and means for coupling said keys to said elements to move them, including a plurality of rods slideably mounted on said frame, said rods extending parallel to one another primarily in a direction parallel to the length of the keyboard but at a small angle with the length of the keyboard, each rod having an outer end coupled to one of said elements to move it and an inner end, said means for coupling also including connecting means coupling the inner ends of the rod to locations on said keys spaced a uniform distance from the axis of pivoting of the keys on the keyboard, whereby to provide substantially the same resistance to depression and substantially the same distance of depression for the keys.
 6. The organ described in claim 5 wherein: said light control means includes a light conducting member constructed of flexible light-conducting material, said member having an edge portion containing a plurality of slits dividing it into a plurality of flexible light conducting fingers that form said elements, the ends of said fingers normally spaced from said pickup regions but deflectable to said pickup region to receive light; and the outer end of each rod lies adjacent to a different one of said fingers, so that when the rod is slid along its length toward a corresponding finger the rod deflects the finger to a pickup region.
 7. The organ described in claim 5 wherein: said elements of said light control means includes a plurality of shutters pivotally mounted on the frame to block and unblock the passage of light between said pickup regions and photocell means; and the outer end of each rod lies adjacent to a different one of said shutters, so that when the rod is slid along its length towards a corresponding shutter, the rod pushes on a shutter portion to pivot the shutter to an unblocking position.
 8. The organ described in claim 5 wherein said means for coupling includes pairs of cam members, one member of each pair mounted on each key and the other mounted on the frame, said cam members extending across one another, and the inner end of a corresponding rod extending substantially perpendicular to most of its rod length and lying between the pair of cam members, so that depression of a key urges sliding of the rod along its length.
 9. The organ described in claim 5 wherein: each of said keys is elongated, extends perpendicular to the length of the keyboard, and pivots about an axis perpendicular to the length of the key; and said means for coupling includes a plurality of cranks pivotally mounted on the frame about axes substantially perpendicular to the axis of pivoting of the keys, each crank having a first arm pivotally coupled to the key and another arm pivotally coupled to an inner end of a rod, whereby the rods help stabilize the positions of the keys.
 10. An organ comprising: means defining a plurality of light pickup regions; means for directing a plurality of light beams which time vary in predetermined patterns at said pickup regions; photocell means responsive to light received at said pickup regions foR generating electrical signals; a plurality of light control elements movably mounted at said pickup regions, each element movable between first and second positions to respectively pass or not pass one of said light beams to said photocell means; a plurality of manually depressable members; a plurality of rods mounted to slide along their length, each rod having an outer end disposed against one of said light control elements, and each rod having an inner end portion that is bent in a return curve which forms a pair of legs spaced along the length of the rod; and a plurality of pivotally mounted linking members, each having a first arm coupled to one of said depressable members to be pivoted by it and each having a second arm extending between the legs at the inner end of a rod.
 11. The organ described in claim 10 including a frame apparatus having first bearings pivotally supporting said linking members about axes substantially perpendicular to said rods, and having a plurality of narrow elongated recesses each extending parallel to a rod and receiving said bent inner end portion of the rod, the second arm of each linking member extending into a corresponding slot.
 12. An organ comprising: means defining a plurality of light pickup regions; means for directing a plurality of light beams which time vary in predetermined patterns at said pickup regions; photocell means for converting light into electrical signals; light conducting means for conducting light from said light pickup regions to said photocell means, including a plurality of elongated light conducting elements individually movable between first positions wherein they carry light along at least part of a path that extends from a corresponding light pickup region to said photocell means and second positions wherein they do not carry light from the light pickup region to the photocell means; keyboard means having a plurality of manually operable keys; means coupling said keys to said light conducting elements for selectively moving said elements in response to operation of said keys; and means responsive to the output of said photocell means for generating sounds.
 13. The organ described in claim 12 wherein said light conducting means includes a member constructed of resilient light conducting material having an edge portion with a plurality of slots therein dividing it into a plurality of fingers forming said light conducting elements.
 14. The organ described in claim 12 wherein: said means defining a plurality of light pickup regions includes means defining a slit for blocking light except along a predetermined path; and said light conducting elements have end portions which lie over and away from said slit when the elements are respectively in said first and second positions.
 15. An organ for use with an optical record comprising: a frame; means for rotating an optical record on said frame; means for shining light through said optical record; means for masking a region at a side of the optical record opposite said means for shining light, except for an elongated pickup area; a light collector having a sheet-like edge portion containing a plurality of slits that divide the edge portion into a plurality of optical fingers, said light collector mounted on said frame with the ends of the fingers near said elongated pickup area; photocell means coupled to said light collector to receive any light picked up by any of said optical fingers; speaker means coupled to said photocell means for generating sounds; and manually operable means for selectively deflecting said optical fingers between positions away from and over said pickup area.
 16. The organ described in claim 15 wherein said manually operable means includes a plurality of rods slideably mounted on said frame, said rods having outer ends adjacent to said optical fingers to deflect them and having inner ends, and said manually operablE means also includes manually depressable members coupled to said rods to slide them along the frame. 